Yup, same experience in Florence. Beautiful city but just couldn't enjoy it. I saw half a dozen other Italian cities and had a great time, Florence was the worst experience and it had little to do with the city and everything to do with the guests.
The one thing that bugs me about museum tours these days is that they all wear in-ear headphones connected to the guide. Which means whereas before you'd mostly have groups of 5 people with one guide, you now have groups of 20 people walking 20 meters behind one guide because distance isn't an issue. Some rooms become unbearable, it's like you take a super busy street market in Mumbai and hang up some paintings and expect people to enjoy the art while navigating through a flood of people.
In a way it helps because you get fewer guides and possibly less shouting. You'd hope this makes things more quiet but it doesn't. It drops the costs of a guide for individuals to next to nothing due to the size of the groups, so you get massive groups and more groups.
Having a few groups of two or three individuals standing around isn't an issue. But when it's a blob of 15-20 people, it's no longer possible to navigate through it or look through/past it, you have to go around and if they're infront of an art piece, you're mostly out of luck.
As for the city, in many parts you hardly hear any Italian and if you do, it's someone in the tourist business trying to sell you something.
I'm not necessarily complaining, I'm part of the problem haha. Just sharing my experience.